Quantitative analysis of trace gases of breath during exercise using the new SIFT–MS technique

.eaP#r# Short r e iereed paper Quantitativeanalysisof trace gasesof breath during exerciseusingthe new SIFT-MS technique sentir. senthilmohanr, DzrnielB. Milliganr,Murray I. McEwanr Colin G. Freemi.rn?, PaulF. Wilsonr l)r:lturtmcrtt,r ol tClt.emical unt!.procc,ts Engineering ctncl:Clrcnr.is,tr.t. U rt istc r,s'i.t.t,rl'f' Cu n t c r h ru-\,,C hr i.;t c lu,trclt, N eiv Ze ctI tut cl Wc slrorv lttlrv tlte concen[rationol'the breath gasesammonia, ilcetone, ancl isoprene vary witli time tlllt'ittgcxet'ciseusitts tlre ttew selecteclion flow tube mas.sspectt'ometry(SIFT-MS) techpiqr"re. The t:rllit'cclllrcltlt ctltlcentratiottsol'amrnclnia.acetoneancl isoprenewere observed witlrin the ralge of -50-'5(X).l(X)-1400 and 5-400 ppb, respectively.lncrensing ilcetone level.swere observecl fbr rnost srrllicctstluring tlte exercise periocl. However, isoprene levels decreaseciwitlr tirne ciuring exercise. o l c l c I s t r l l i e u t .s h o w e d l r i s h e r l e v e l s o l ' i s o p r e n ec o m p a r e d w i t l r y o u n g e r s u b j e c t . s . The anrmo'iir I t t r l c . P t ' o l ' i lrcv i t l r o x e t ' c i s cs l t c l w e cll o t h c l e c r e a s i r ragn c li n c r e a s i n gp a t t e r n s l b r c l i f t ' e r e pst u b i e c t . s . IN'TROI)UCTION P,,rrIeNrs AND METI-IoDS 'l'lrc: sclcctcd iorr I'lclw tube r"nltss spectronretry ( s I I " 1 ' - - - N 4 st c) c l r r r i c ; u lci r r n r r a l y s i n gt r a c ec h e r n i c a l . s irra s i r r g l ch r c u t l rc x h a l a t i o r ri s b a s e do n s o l ' tc l r e r n i c a li o n i s a t i ' r r o l ' r h c t r a c c g a s e st o t h e c x c l u s i o n o f t l r e r n a . l o r llrcrrrIh g i l s c s ; l.n i r I ' n s t - l ' l o w i n gi n e r t c a r r . i e rg a s , t h e i u r . . r r r o l c c r r l cr c l r c t i o r r so c c L r rl ) e t w e r1: 1t h e t r a c eg a s e sa n d t h e 'fhe P l c - s c r l c c l c r; rl rl c c r r r s o ri o r r s I - l 1 o no r o . ' - . instnrment i s l r i g l r l _ r , s c r r s i t iuvncc lr e u c l i l ya b l e t o - i c l e n t i l yt h e ltroci_ u c t s o l l c a c t i o r r sl ' r e t w e e ri rn . j e c t e ri lo n s n r r cti l r e t r . a c en e L r _ t n r l r c r r c t i r n tr r r o i e c u l e s .I r a s t o r r - l i n e c l a t a a c c r u i s i t i c l n Iurrclrv:rrc:Lncis<ll'twureure useci to lnalvse the ,nass sl)cctl'ilobfairrecl.In tlur lalt0ratorv,lve have cletectedanci c F r a n t i l ' i c c{ lr ' u c eg i r s e sl i ' o n r 5 p p b u p t o 4 0 p p r n . S i n c c t l r c t i r r r c i n t c n , a l l t l r t w o c o n s e c u t i v ea n a l y s e sr e c l u i r e s t o s s l t l L n u s c c o r r r l ,i r s y s t e r nr n n y b e n r o r r i t o r e <cJo n t i n u _ ,Lrslv. r\ schernzrt.ic cliaqrarl ol'the cantertrury SIFT-MS I r l l l l i l l ' i t t u iss s i r o w r ri r r F i g u r . el . A g r o u p o l ' 5 r n a l e s a n d 3 l " e r n a l e s( a l l h e a l t h y n o n n a l athletes - cyclists, long ciistaltcerllllners, anci sprinters) l)articipateclirr this study. The age range of the subjects wa.s l5-10 year.s.All exerciseri by r-unningexcept one cyclist lvho cycled. Trace gases in a single exhalecl breath tvere rneasured by SIFT-MS ancj several such breatlrswere averaged. In the SIFT-MS, chemical ionisation was acirievecl using alt O"'' l)t'ecut-sor selectedusing a cluaclrupolernass f i l t e r a n d i n j e c t e c li n t o a l r e l i u m s t r e a m ( 0 . 5 T o r r , 2 5 - r 5"C) using a ventut'i orifice.r The breath gas was aciclecl lnrther downstrenm a[ a consicierably lower f]ow rate (-3.5 Torr L s-r). The ion product.swere analyseclby a secorrdcluadnlpolelnass filter and counted by a continuous clynodetype ltarticie multiplier. Rgsut-rsANDDISCUSSIoN l i c c ' c i v c tIl l ) c u e l n b elrt j g t ) r \ c c c p t e t l| 7 l ; c l t r t r l r l yl . ( X X ) ( l r r r c r s l l r r r r r l c ntc( )e:l . ' r r r li'\.4 . 1 M c E w a n .D e p a r t n r e rot tl c h e r u i s t r y , l)r'i" lc l tlrs 4fi()0. [-lrri versity . l' canterlrLrr-y, Christchurch,New Teal.ltrtl ' l ' c l :- t - h J . l i 6 4 l i i 7 . 5 :l ; l x : + ( r 4j i 6 4 2 | l 0 Ii- rrtl i i : rrr.rrrcorvr rn (rjrcltertt.ci.r rtLet-btt rv.nc.rtz l i t ' r l u r l i t ' r t r t r ' t \. t r l . . i . Nos l/3. l(XX) During strenuous,j*.r.ir.. phosphagenanciglycogenlactic acid systernscAlt ltrovidemaxilnzrlmusclepower 1br a period of 8-10 s ancl t.3-1.6 rnin, r-espectively.2 However,the aerobic.system providesenergyfbr as long as nutrientslast. The aerobicsysternis r-equired1br prolonged athleticactivity and those wirich burn glucose, latty acid and those amino acicisin the rnitochondriato provideenergy. O W. S. Maney & Son Ltd I 52,\t'ntli.lntolt.an, Mi.Lhqan,McEvtcm, Freenmn, WiLson i.lcu1r:rIiniet lirr l'krrvingu iteralorv ( lr l prt:clrl "-ur gltrinht) Rerction 1'lorv t oots Blotvt:r f I I t jrllct, lvcnfull inlct) I'i f" tht ctpill:u'y lbr thr I-Ieatr:'dctpill:u.y l-Ieatr:'rl g,;rs illrodudJoulflfie {/ ii . , . / : l l l i - l // \ 'r-\ llt:girrn i; w " . . . . . . . _ . - . - . - . r - - .l .". i . / -\rrl l] 'I- Spccfrorncler.- ,/ i r ./ r l l l ) | ; I ) i r l I i -I" J " rliflirsion rliflir*ion I i l I r i i i I t i r I i i i lilcctnrsl:rticl.,cnscs IonSr:lcr:lion I , ' ( . l r r : r r r r u p ' r c v r ^ r r 7I / / 1 I p,, tlii'l\rsirn t ) u .- . i,;,,.---"*-/-i ll r it Ion ( :r ' c i t l l t ) t l i I I r-_l t jll_!I,-.: liirll \, I i snmpre. i / / t l Root"' Blorver t l l l ) r l i i l - _- * - - - _ * _ - _ . ; ll.c:rclionlr'trrr, _,. _ ___i 1 lirbc --l)ctcctirtn ltcgirrn ------.1 I It t:giort l , ' i g . l , , \ s c l r c u r i r t i cr l i i r g r l r u or l ' t l t c s c l u c t c t l i o n l ' l r l w ( t t l t ct t r i t s s . \ l ) e c t r o l ' l l e t(f.yS l l " - f - M S ) . l,s'o1trt' rrr' I i rttt' ltrr4lilc,s'tvi.tltcxc t'ci.vc l)r'c-cxcrcisccxpirccl .isopreneccltrccntratiottwas olrservc(l l)Lltwcen55-lii5 ppb lr.rrthe sulrjects(Fig. 2). The i s o l l r c r r ce o r r c c n t r t t l i o ct tl e c r e a s ed l t r i n g t h e t i r n e o l ' e x e r * d ithin c r s c . z \ r r r i r r i r n r r r lrer v e l o f i s o D r e n ew i . t st ' e c o r c l e w the rangeol'0-40 ppb lbr all the strbjectsafter20-30 rnin vety low (lessthan 13 aucl3 subjectssh<-lwed cll'exercise initially declinedbut ppb)levets.lsopreneconoentrations thenexhibiteda slow rise with the rernainingtirneof the ip ail the cxercise.This interestingpatternwas obset"ved suLr,jects. L U .'/ t/{' 40 TirneIminl l i i t : . ] . l s ( ) t ) t - u r ct r r o l i l c s r v i t i r e . r . e t ' c i s e 70 dttring exercise:new SIFT-MS technique 153 etnn.titath,eanal),sisoJ'trace gaseso.f'brcath Isoprette is tlost likety tbrrned as a by-product of the llios_Vrrthesis of isoprenoid cornpounds, or their decomltotfi. rlr A small alrlounI of breath isoprene lrctsitirtrr. ntight ilrisc fronr llefoxidatiou of the cholesterol precursor..squalcrre.Isoltrene excretion predotnilantly via the Igngs r-esultsfrorl its low wa[er solubility and low $oilipg pgirrt. Sgpre literature studies also fuaveconfirmed tlrirt [rreutlrisopretreis linkectlo cholesterol biosynthesis, wlrich relies ott l-[tettrevalonatepathway. /\rnrrrrtrrirtti mc pnfi l.asvvitlt'cxerci'sc A s i r r r i l a rl-t u t t e r nw n s o l l s e r v e c fl b r a m u r o n i aa s f o r i s o (r sLrfi.jccls.I-lowever for 2 other subjects the ltrepcr irr i r n t o L t not l ' l l t u t . t o r t i r ct x p i t ' e c il n i t i a l l y i n c r e a s e da n d t h e n I'cll. Arrrrnortiit uotrcetttrAtiCrnWilS ObserVed betWeett .50-.i(X)pph clur.irrgtlre cxercise. Since Iro tbod restricti1lrrsrvc;c lpltliccl to tlte str[.iects.Inore protein intalce ugulcl bc ;esltottsillle 1br the elevated amtnouia levels r l u c t o t h e o x i c l a l i o t tt l 1 ' t h ea t n i n o a c i d s ' r t\ t' t'I rt t tc t i rtt c p rrli l.c,s'w i.th. axerc i':;e Irrcrcusttttlitccttltto levels were olrserved with exercise; lltc t'atesol'ultitttgein acetonelevels (l(X)-t4(X) ltorvc:\,rjr'. plpicl irs tlre charrgesobserved lbr iso1l1tlt)r.rrc;cllot us '[he rise in brcath acctolleIevels lcvels. l)t'ctrcot' iu'l'lnlotttit tcl'lcclslhc ittcreltscirr 1'attyaciclcatabolisttrits a sottrcecll' cnct-g)/lirr. tlre sul.ljectsduring the clbserveclperiods clf cxcr-cise.Sincc the acetonelevel is relateclto t4t $utning tlirrrug[ tlte ircclyl-CtlA pathwity, a continuous it1creaseof Ircctonc with the titne rlf exercise is nn indicatOro[ lat sltowed an iucreitsedconcentralrrr;rri1g. u\ll t[e sgl-r.iects (iorrwrtlr Lirlc witlr excepticln01'3 subjeotswhere an initlirt rlccrelse w1s observecl.Afier continued vigorous exercisc lirr'()0 rurrr,irthletesshttwecllrrofe tlrertla 2-fblcl increasein lcvcl. Otlrers ltave slrown that enhaucedlevels llrc:ircc:torrc trlsoohscrvedatier lttsting.l tvcl'e ol'ircctortc CoNct-usloNs The sIFT-MS technique is sensitive, rapid and accurate, anclrneasuresabsoluteconcentrationsof the tracevolatiie specieson human breath.The techniqueis broadly applicable to clinical meclicine,biology, tbod analysisand environmentalrnonitoringAlthough this applicationof the techniqueis somewhat exploratoty in nature, it has successftillydemonstrated that metabolicprocessesin exercisingathletesafe readiiy accessibleto real time monitoring.Further measul€ments are recluireclon a larger sampleof athletesbetbre the ftill parttemof rnetabolicchangeemerges.We lre hopeful that ihe techniquewill leacito a .sensitiveindicatorof caldiovascularfitness. \CKNOWLEDCEMENT we gratetirlly acknowleclgefinancial sr"rpportfr-ornthe Nelv Zealand. MarscleuFr-rnd, RrpgRgNcgs L 2, spunel 11suritlr D. Selectecliou ['low tttbe:tt technicluelor qtrarrtitative trilcegas analysisol'air attd breath.MeclBictl Dn1; Compttt 1996;34: 409-419, edn' of.Mcdicttl Pltv,tkll'tl1i1,,8tlr At.thurC' Guyton MD. Tc.uthtlrlk l99ll tl4: 940-950' Lonclon:W B Sarrrttiers, in 3 , S y l a n ePl , D a v i e sS , S m i t t rD . Q u a n t i l ' i c l t t i oon[ ' t t m m o n i a rrurrrtnlrreathby tlreselectedi0n l'low tu[reartalyticaitnetltod ttsingI{.O'nnd O,n precursorirtns'RctpitlComnuutMass ,\1tct:tntnr19981t2: 763-766' mass 4. t-ildirrger w FlanselA, JorclanA. Proton-tratrsl'et'-r'eaction spectroutetry(PTR-MS): on-lirtetnottitoringol volatile orgaltic at pPtv level.s.ClrcmSoc llev l9c)8i27:347'354' crrtrrprtrtnc.l.s